Weatherwatch: March/April 2010

Following an extended period with little concern about drought east of the Rockies, dryness developed or expanded during March in several areas, including the Great Lakes States and the central Gulf Coast region. In contrast, three major March storms (along with another system in late February) induced several rounds of flooding in the northern Atlantic coastal plain. Hardest hit were Rhode Island and eastern Massachusetts, where record-setting monthly precipitation totals of 10 to 18 inches were common. Interestingly, most of the precipitation fell in the liquid form, with snow mostly confined to higher elevations of the Northeast. Flooding also affected the Midwest, mainly from the eastern Dakotas into the middle Mississippi Valley, due to the melting of an extensive snow cover. Elsewhere, highly variable conditions existed across the Plains and the West. For example, the Rockies received significant precipitation, which was especially beneficial in the drought-affected northern mountains. California, however, experienced a disappointingly dry March, following an otherwise adequate wet season.

Meanwhile, unusually warm temperatures across much of the nation's northern tier contrasted with cool conditions in the South. In fact, record-setting March warmth (locally more than 10°F above normal) affected the upper Great Lakes region, while record-low March temperatures (more than 5°F below normal) were noted in parts of Florida.